The red circles are centred on HQ and Clearwater Mall, and have radii of 90.2 km and 51.5 km respectively.
The blue markers are the route endpoints from travelling outwards by road from the centre of each circle, using the circle radius as the maximum travel distance. The green marker is the current midpoint between the start and endpoint, used for the route calculation. The gray squiggly line is the current route calculation.
The blue polygons that are created by the blue markers indicate the maximum distance you can travel by road, using the circle radius as the target distance.
Where the blue polygons intersect in the Muldersdrift area, is where I guessed the Year End function to be. Given another starting location, say Centurion, and the distance from it to the venue, the calcuation could have been more accurate.